Rotary connector

Abstract

A rotary connector includes a case, a cover, a rotor having a top panel part and a first cylindrical part, a rotor snap having locking parts locked with an outer surface of the cover and a second cylindrical part snap-fitted to the first cylindrical part, flexible cables wound windably/rewindably in the case, and a ring-shaped plate part. In this case, a holding projection project outward in a radial direction from the outer circumferential surface of the second cylindrical part between a lower end of the first cylindrical part and the locking parts, and an inner rim of the cover is provided with a holding step so as to form a step. Furthermore, a wall surface forming the step of the holding step faces side surface of the holding projection, and an inner rim of the cover is rotatably interposed between lower surface of the holding projection and an upper surface of the ring-shaped plate part.

1. A rotary connector comprising:
 a fixed-side housing that includes a cylindrical case and a ring-shaped cover for covering a lower open end of the case; 
 a movable-side housing that includes a ring-shaped top panel part for covering an upper open end of the case and a first cylindrical part protruding downward from an inner circumferential end of the top panel part; 
 a rotor snap that includes a second cylindrical part connected to the first cylindrical part by being inserted thereinto from under the cover and locking parts having segments protruding outward from a lower end of the second cylindrical part in a radial direction thereof; 
 a receiving space that is formed by rotatably assembling the movable-side housing to the fixed-side housing; 
 flexible cables that are electrically connected to the fixed-side housing and the movable-side housing in the receiving space; and 
 a ring-shaped plate part that is locked with the locking parts; 
 wherein a holding projection projects outward in a radial direction from an outer circumferential surface of the second cylindrical part between a lower end of the first cylindrical part and the locking parts, and a holding step is provided so as to form a step on an inner rim of an upper surface of the cover, and 
 a wall surface forming the step of the holding step faces a side surface of the holding projection, and an inner rim of the cover is rotatably interposed between a lower surface of the holding projection and an upper surface of the ring-shaped plate part. 
 
   
   
     2. The rotary connector according to  claim 1 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis. 
 
   
   
     3. The rotary connector according to  claim 1 ,
 wherein a ring-shaped holder, which rotatably supports rollers for reversely winding the flexible cables, is rotatably received in the receiving space, and an inner rim of the ring-shaped holder is rotatably interposed between a lower surface of the first cylindrical part and an upper surface of the holding projection so that the ring-shaped holder is rotatably supported on the second cylindrical part. 
 
   
   
     4. The rotary connector according to  claim 3 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis. 
 
   
   
     5. The rotary connector according to  claim 3 ,
 wherein the ring-shaped holder is provided with an elastic part for elastically biasing the upper surface of the cover. 
 
   
   
     6. The rotary connector according to  claim 5 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis. 
 
   
   
     7. The rotary connector according to  claim 1 ,
 wherein the cover is provided with an engaging step so that a step is formed on an inner rim of a lower surface of the cover, and a wall surface of the engaging step faces a side surface of the ring-shaped plate part. 
 
   
   
     8. The rotary connector according to  claim 7 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis. 
 
   
   
     9. The rotary connector according to  claim 7 ,
 wherein the ring-shaped holder is provided with an elastic part for elastically biasing the upper surface of the cover. 
 
   
   
     10. The rotary connector according to  claim 9 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis. 
 
   
   
     11. The rotary connector according to  claim 3 ,
 wherein the cover is provided with an engaging step so that a step is formed on an inner rim of a lower surface of the cover, and a wall surface of the engaging step faces a side surface of the ring-shaped plate part. 
 
   
   
     12. The rotary connector according to  claim 11 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis. 
 
   
   
     13. The rotary connector according to  claim 11 ,
 wherein the ring-shaped holder is provided with an elastic part for elastically biasing the upper surface of the cover. 
 
   
   
     14. The rotary connector according to  claim 13 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis. 
 
   
   
     15. A rotary connector comprising:
 a fixed-side housing that includes a cylindrical case and a ring-shaped cover for covering a lower open end of the case; 
 a movable-side housing that includes a ring-shaped top panel part for covering an upper open end of the case and a first cylindrical part protruding downward from an inner circumferential end of the top panel part; 
 a rotor snap that includes a second cylindrical part connected to the first cylindrical part by being inserted thereinto from under the cover and locking parts having segments protruding outward from a lower end of the second cylindrical part in a radial direction thereof; 
 a receiving space that is formed by rotatably assembling the movable-side housing to the fixed-side housing; 
 flexible cables that are electrically connected to the fixed-side housing and the movable-side housing in the receiving space; and 
 a ring-shaped plate part that is locked with the locking parts; 
 wherein a holding projection projects outward in a radial direction from an outer circumferential surface of the second cylindrical part between a lower end of the first cylindrical part and the locking parts, and an inner rim of the cover is rotatably interposed between a lower surface of the holding projection and an upper surface of the ring-shaped plate part, and 
 the inner rim of the cover is provided with a wall surface forming a step that faces a side surface of the holding projection or a side surface of the ring-shaped plate part with a small clearance. 
 
   
   
     16. The rotary connector according to  claim 15 ,
 wherein an engaging step capable of receiving an outer circumference of the ring-shaped plate part is formed on an inner rim of a lower surface of the cover, and a wall surface forming a step of the engaging step faces the side surface of the ring-shaped plate part. 
 
   
   
     17. The rotary connector according to  claim 15 ,
 wherein a holding step capable of receiving outer circumference of the holding projection is formed on an inner rim of an upper surface of the cover, and a wall surface forming a step of the holding step faces the side surface of the holding projection. 
 
   
   
     18. The rotary connector according to  claim 15 ,
 wherein the ring-shaped plate part is detachably locked with the locking parts and includes a cam part protruding downward in a direction of a rotation axis.